Bug 12615: Remove CGI::scrolling_list from marc_subfields_structure.pl

Bug 12615: Remove CGI::scrolling_list from marc_subfields_structure.pl

This patch removes all instances on this file.

Also re-enable editor feature to show/change kohafield value, can't find when or why it was removed.
Up to QA or RM for consideration, simply to remove.
But is strange to have a non editable field on auth frameworks.

To test:
1. Apply the patch
2. Go to Administration > MARC frameworks
3. Clic MARC structure of any auth fw
4. Clic subfield on any tag, e.g. 020
5. Clic 'Edit subfields' button

Now the tests proper

6. On any subfield, check pulldown
'Managed in tab', was replaced, so test
if it works and search for regressions
Change, save, load, change again

7. Clic on 'Advanced constraints'
(2) scrolling list removed
At the bottom, check 'Koha link', was changed
Check assign/remove/save/load values, search for regressions

8. Clic on 'Other options' box
Eight(6) scrolling_list removed, they use to
feed three pulldowns, so check each one

'Authorised value',
'Thesaurus'
'Plugin'
Check assign/remove/save/load values, search for regressions
Check adding a new subfield

Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Passes all tests and QA script, no regressions found.

Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>